Authors & Affiliations
Zagorulko Yu.I., Ganichev N.S., Zhmurin V.G., Kasheev M.V.
A.I. Leypunsky Institute for Physics and Power Engineering, Obninsk, Russia
Ganichev N.S. – Research Engineer I category, A.I. Leypunsky Institute for Physics and Power Engineering.
Zhmurin V.G. – Lead Engineer, A.I. Leypunsky Institute for Physics and Power Engineering.
Kasheev M.V. – Senior Researcher, Cand. Sci. (Tech.), A.I. Leypunsky Institute for Physics and Power Engineering.
In the article there are presented results of investigation on the final state of 19-rods subassembly mock-up after simulation experiment in conditions of unprotected lose of sodium flow rate. Experiment was carried out on the installation “Pluton” at initial sodium temperature of 823 K. Corium was simulated by a melt of thermite reaction products (Al2O3+Fe, T ~ 3100 K). Along with overall picture of fuel pins simulators degradation there were investigated final distribution of materials on the subassembly height, blockage phenomena and materials release out of subassembly volume. Experimental data analysis has shown that principal mechanisms of fuel pins simulators claddings degradation could be referred to temperature stresses and material melting. Dynamic effects, caused by sodium/corium thermal interaction,are responsible for materials final redistribution inside of the subassembly and their release out of subassembly volume (80-85 % as referred to thermite mixture initial mass). There was detected almost total blockage of the subassembly bottom part. Composition of the plug materials corresponded to that of fuel pins simulators claddings.
melting, degradation, fuel assembly, accident, nuclear reactors on fast neutrons, security, thermite, corium, blocking the flow cross section, thermal interaction, distribution of materials
1. Kovaliov Yi.P., Zagorulko Yu.I., Zhmurin V.G. Teplovye effekty pri gorenii termitnoy smesi U+MoO3. [Thermal effects at thermite mixture U+MoO3 combustion]. Preprint FEI 2745 - Preprint IPPE 2745. Obninsk, 1998.
2. Zagorulko Yu.I., Kasheev M.V., Ganichev N.S., Zhmurin V.G. Issledovanie razrusheniya imitatorov tvelov v staticheskom natrii pri peremennykh teplovykh nagruzkakh [Investigation on fuel pins simulators degradation in static sodium at transient heat loads]. Doklad na Rossiysko-Frantsuzskom soveshchanii rabochey gruppy RG-3 "Tekhnologiya" [Report at Russian-French meeting of working group RG-3 "Technology"]. Obninsk, 2014.